The present invention relates to a hologram generation apparatus and a hologram generation method, and in particular to a hologram generation apparatus including a spatial light modulator unit and a hologram generation method.
A hologram generation method using a liquid crystal display panel or the like as an SLM (Spatial Light Modulator, Spatial Light Modulation element, or Spatial Light Modulation device) has been known as disclosed in, for example, Japanese Patent No. 3593359 (hereinafter referred to as Patent Literature 1). In this method, a hologram is generated by generating object light by modulating the amplitude and the phase of light branched from a yardstick light source (or a reference light source) by using an SLM, making the other light, i.e., reference light branched from the yardstick light source interfere with the object light, and performing exposure with the interference fringes. Patent Literature 1 has a characteristic feature that it can generate a unique hologram by generating object light by using a successively-rewritable liquid crystal display panel without using an original plate.
Meanwhile, a method for generating a relatively large-sized hologram (a multi-layout hologram) by forming a plurality of partial holograms disposed adjacent to each other has been known as disclosed in Japanese Patent No. 3608747 (hereinafter referred to as Patent Literature 2). In Patent Literature 2, in order to make a seam between adjacent holograms inconspicuous, the seam between holograms is formed by a group of different straight lines or different curved lines, instead of forming it by one straight line.
As another example, when a wiring pattern is formed on a silicon wafer in a semiconductor manufacturing process, a technique for smoothly connecting joint parts in the pattern by adopting a so-called “connecting exposure” is used when the entire pattern cannot be covered by one exposure range, though it is not a technique for generating a hologram.